Lessons in being human
by forbidenlotus
Summary: Though he has watched them for years, Castiel still doesn't completely understand the humans he watches over. Lucky Sam and Dean are there to give him some pointers. Just plan sensless humor marked t for language. No slash.


I do not own Supernatural. Just a broke fan.

 **Chapter 1 Nicknames**

I stared at the blinking motel sign with fascination. This was the third motel I had 'visited' yet all seemed to display gaudy signs such as this. Interesting. A loud crash drew my attention away from the window to witness Dean, half-awake, collapse into a chair in front of the plate of food he had slammed before him. He winced when his actions caused the wound in his shoulder to send a sharp pain through his arm, but apparently, the pain was quickly forgotten in favor of the food. I had been traveling with the two brothers for a week now. Dean had been stabbed by a witch in a small town named Punxy. The weapon was bewitched so that even my angelic healing could not close the wound. Therefore, I received orders to keep close watch on the pair as it healed. Of course, I could have observed from afar, invisible to the human eye, but I found that my vessels presence was a more efficient deterrent that my true form. Dean was more reluctant to do something stupid when he could see me watching him. Marginally. Hence, the week long journey.

"Looks like we got a cluster of omens in Old Town, two miles from here." Sam stated from where he sat at the table, scanning one of the newspapers in front of him. "Lightning storms, failed crops, the works."

I glanced at Dean who emerged from the pork product he was currently devouring to look at his brother. "Think it might be connected?" He asked skeptically. " I mean Old Town is a little out of the way from Lilith's last little demon nest, isn't it?"

"Yeah, but when do demons tend to stick to one area. I mean wouldn't now be the best time to investigate considering. . ." Sam's eyes glanced my direction before firmly fixing onto the table. With my limited interactions with Sam, I have noticed his tendency to regard me with a level of fear, awe, and weariness, not surprising considering his history with demons. He behaved as if he expected me to turn and strike him down with the littlest provocation. I could understand his trepidation though its side-effects were counterproductive to our interactions. I did my best to ignore it.

His brother held no such fears of me. "Bring a little heavenly wrath down on their asses. I'm game. What do you say Cas, you in the smiting mood. . . Cas?" His eyes indicated that the question was aimed at me.

"Cas?" I repeated. I was unfamiliar with this word.

Dean's face mirrored my confusion for a second before shifting. He looked at me as he did Sam when the boy said something particularly thoughtless. "Yeah, Cas, Castiel, I'm talking to you. What do you think? Should we go check it out?"

"Why did you do that?" I interrupted, and Dean's face changed again. This time creeping towards annoyance.

"Do what?" he asked.

"I think he's asking why you're calling him Cas." Sam interjected hesitantly, causing Dean to roll his eyes.

"I know what he's asking. Cas, short for Castiel. Now what do you think about. . .?"

"Why are you shortening it?" I interrupted again, my curiosity rising. Humanity, I had found, was full of small mysteries such as this, something that even my centuries of guarding did little to explain. But if I was to blend in on earth in this vessel, I had to make an effort to understand them.

"What do you mean why? Cas is quicker than Castiel. Its easier. Don't you angels ever do that. You know, call your brothers mike or gabe while you flutter from cloud to cloud doing whatever you do when your not being a pain in my ass?" His voice began to rise. Yes, definitely annoyance.

"No," I responded, keeping my voice level. "We were named by God. Our names are a gift and an honor. To shorten it would be disrespectful to the one who named us. Did your parents not name you Sam and Dean for a purpose?"

Sam chose this moment to join our conversation. "Actually, my name is not Sam. Its Samuel, but lots of people call me Sam for short because. . ."

"Save it, Sammy." Dean interrupted. "Look, I called you Cas. Its shorter than Castiel and much less girly. Can we just move on. . ."

"You're offended, because you believe my name is feminine?"

He just stared at me for a breath before throwing his hands up. "You got me. I hate girly names. So, can we please just get back to the . . ."

"Then, why do you call your brother Sammy?" I queried, plowing through his obvious displeasure.

Confusion momentarily cut through Dean's anger. "What?" Sam. . . Samuel looked equally confused.

"Sammy, I assume, can also be used as an abbreviation for Samantha." I replied in explanation.

"Yeah, well I call him that sometimes too. He's a man of many names." Dean replied dryly. At my confused look, his aggravation reached its peak, and he stalked towards the door. "I'm going out to get some supplies. " He grumbled before slamming the door behind him.

I turned back to Samuel, who was smirking in his brother's direction. The expression inevitable melted into guilt when his eyes met mine. " I believe I upset him." I stated.

Samuel snorted. "Not upset, embarrassed. Look think of Cas as a sort of nickname. A name that only those closest to you call you, such as your friends and family." He elaborated, "Its a way we humans express affection and familiarity."

"Ah," I responded, feeling a strange flicker of joy at the word affection.

Samuel's smile flickered back for a moment before his awkward shifting returned. "Well, I better go check on him before he does something stupid." he stated, clearly uncomfortable being alone in the room with me.

I nodded sympathetically, musing. "Your brother does have that tendency." I stated truthfully. To my surprise, he laughed. " Yeah, tell me about it." He responded, smirking. I smiled softly in return. Shifting for another moment, he glanced at me once more before reaching for the door. "Thank you for the explanation. . . Sam." It felt strange address him that way, knowing his full name but it was worth the reaction.

His smile widened, genuine and unafraid. "No problem, Cas."

I nodded in response and watched him close the door and run to catch up with his brother.


End file.
